This application claims priority of Korea patent Application No. 2001-0007088, filed on Feb. 13, 2001, the content of which is incorporated herein by reference.
(a) Field of the Invention
The present invention relates to an aqueous ink composition with metallic glittering, more particularly to an aqueous ink composition with metallic glittering having an excellent glittering appearance, three-dimensional effect, and smooth writing performance.
(b) Description of the Related Art
In order to obtain handwriting having metallic luster such as a gold and silver, various aqueous ink compositions have been proposed using glittering pigments. For example, an aqueous ink composition using aluminum powder pigment was proposed in Japanese Patent Publication No. 7-118592, and an ink composition using pearl pigment was proposed in Japanese Patent Publication No. 8-151547. Japanese Patent Publication No. 11-29734 also proposes metallic aqueous ink prepared by coloring aluminum powder with an organic pigment using a fixer. However, in the case of conventional aqueous ink compositions of prior art, the use of glittering pigment such as aluminum powder pigment, and pearl pigment and the like, can obtain a glittering appearance and three-dimensional effect, but it is not to a desirable level. Also, other methods have been adopted using a coloring method applying colorants such as dyes and pigments, in order to obtain a metallic color, however, this method also results in a loss of glittering effect due to the use of resin during the coloring step.
To resolve the above problems, EP No. 1,038,931 proposes a technique improving the metallic luster of the ink composition using an inorganic pigment coated with a metal. However, because the aqueous glittering ink composition prepared by the above method uses metal-coating inorganic pigment of a large density, it deteriorates the writing aptitude due to the increase in the weight of the ink composition, and has a high possibility of a precipitate form in storage.
It is an object of the present invention to provide an aqueous ink composition with metallic glittering having a strong glittering appearance greater than the ink composition of prior art, simultaneously having an excellent dispersible nature, without the possibility of a precipitate form due to the light density of the ink composition, as well as handwriting having a vivid three-dimensional effect, or coating film, which is unobtainable in conventional ink compositions.
In order to achieve the above objects, the present invention provides an aqueous ink composition with metallic glittering comprising a metal-coating resin component, a colorant, a water-soluble resin, a water-soluble organic solvent, and water.
The present invention is described in detail as follows.
The present invention, in order to increase the metallic glittering property, can provide an excellent handwriting or coating film art by using a metal-coating resin component coated with more metal than is generally used in aqueous ink compositions having glittering pigments of prior art.
The present invention can also reduce the weight of the ink composition and improve the dispersible nature, due to the use of a metal-coating resin component having light density and small particles, compared with the method using metal-coating inorganic pigment in EP 1 038 931.
The aqueous ink composition with metallic glittering of the present invention comprises a metal-coating resin component, a colorant, a water-soluble resin, a water-soluble organic solvent, and water.
The metal-coating resin component is composed of closely adhering and laminating mutually soluble resin coating film and metallic deposition film, which has electro-conductivity due to the coating of the metallic deposition film. These are composed of closely adhering and laminating mutually metallic deposition film/resin coating film, or resin coating film/metallic deposition film; or may be prepared by repeatedly coating a constituent unit of metallic deposition film/resin coating film. Also, the present invention can prevent falloff of the metallic luster by inhibiting the extreme agglomeration of metallic deposition film closely adhering and laminating a second resin coating film on the resin coating film/metallic deposition film.
These metal-coating resin components may be prepared by a conventional coating method such as the Roll coating method, the Gravure coating method, the Reverse coating method, and the spray coating method etc. An example is described as follows.
First, in order to coat the resin coating film layer on a base film, a suitable coating solution is prepared, and a metallic film is formed by depositing the metal on the base: the metallic film is a closely adhered to the resin coating film and metallic deposition film mutually. Then, the metallic film is peeled and grinded from the base film, and as a result, the metal-coating resin component may be obtained.
In the method above, the resin coating film is coated on the base film applying a release layer, and metallic deposition film is formed on the above film, and then a metal-coating resin component having resin coating film on above and below the metallic deposition of the surface may also be obtained by coating the resin coating film as the same resin coating film or the second resin coating film. In the above method, the resin coating film is coated on the base film applying the release layer, and metallic deposition film is formed on the above film, and then the metal-coating resin component having a repeat unit of resin coating film/metallic deposition film also may be obtained by repeating the same procedure many times, preferably three times.
The base film supports the metallic film formation, and preferably the base film is used, which is inactive in the coating resin. The example of the embodiment of the base film comprises resin such as polyester, polyamide, polyethylene, polypropylene, cellulose acetate, polycarbonate, polyvinyl chloride, fluorinated resin etc.; and cellophane etc.
Also, the release layer more easily releases the metallic film from the base film, which can be used to thermoset the silicone resin as an inert film for the coating resin.
In the present invention, a resin for the resin coating film dissolves in water or organic solvent of ink composition of the present invention, it is preferably the same as the water-soluble resin of the ink composition or resin having compatibility with the resin. For example, the resin may be used, at least one selected from the group consisting of polyvinyl chloride, vinyl chloride, nitro cellulose, cellulose acetic acid, ethyl cellulose, polyvinyl alcohol, casein, gelatin, vinyl chloride-vinyl acetic acid copolymer resin, butyral resin, acryl resin, polyamide resin, polyester resin, and epoxy resin.
The thickness of the resin coating film is from 0.1 to 5 xcexcm, more preferably from 0.5 to 3 xcexcm. Wherein, if the thickness is less than 0.1 xcexcm, it may not obtain a suitable metallic luster due to the difficulty of continuously forming the resin coating film. If the thickness is more than 5 xcexcm, in the case of the application in ink, paint, and adhesive and the like, there is a lack of metallic luster and falloff of electro-conductivity due to the small ratio of metal component among the total composition.
A metal coating in the resin component may be used, at least one selected from the group consisting of gold, silver, aluminum, copper, nickel, zinc, potassium, indium, and chromium, or metal oxide may be used, such as alloy metal comprising stainless steel or tin oxide, and indium oxide etc. Preferably, when aluminum and copper are used, it has the effect of a metallic luster, electro-conductivity, reducing costs etc.
The coating thickness of the metallic deposition film is 0.02 to 5 xcexcm, wherein if the thickness is less than 0.02 xcexcm, the content of the metallic deposition film relative to the content of the resin coating film becomes few, therefore it is difficult to obtain an expectative physical properties in case of application as ink composition. If the thickness is greater than 5 xcexcm, it is uneconomical and difficult to grind due to the use of many metals, also it is difficult to disperse in case of application as the ink composition.
The metallic deposition carried out by the conventional metal coating formation methods such as vacuum deposition method, sputtering method, and ion fretting etc., can result in the metal-coating resin component.
Also, the resin used in the second resin coating film is an insoluble in the ink composition of the present invention, and prevents the loss of a metallic brightness characteristic. The resin may be coated anywhere above and below the surface of the metallic deposition film, wherein the resin may be used all the resin that the characteristic of the ink composition is not reduced. For example, the resin comprises thermoplastic resin, and thermosetting resin etc., more preferably is at least one selected from the group consisting of acrylic resin, vinyl chloride-vinyl acetic acid copolymer resin, polyvinyl butyral, polycarbonate, urethane resin, urea resin, melamine resin, urea-melamine resin, epoxy resin, alkyd resin, amino alkyd resin, and rosin modified maleic acid resin. The second resin coating film is also coated from 0.1 to 5 xcexcm, more preferably 0.5 to 3 xcexcm as the same resin coating film.
The metal-coating resin component prepared in this way may display a metallic luster effect such as silver color, gold color, red color, blue color, green color, and purple color etc. An average diameter of the metal-coating resin component is preferably 5 to 200 xcexcm. If a diameter is less than 5.0 xcexcm, it is not preferred as the glittering effect is reduced by the resin component particles being too small. If the diameter is greater than 200 xcexcm, when the metal-coating resin component is used in ink type for ballpoint pen, the ink from pen tip is difficult to flow.
In the present invention, the amount of the metal-coating resin component is preferably 0.01 to 40 wt %, more preferably 0.5 to 30 wt % relative to total ink composition. If the amount of resin component is less than 0.01 wt %, the glittering appearance is not satisfied. An amount of resin component more than 40 wt % is not preferred as it reduces the fluidity due to the viscosity of ink being too high.
Also in relation to the ink composition of the present invention, a metal-coating resin component may be used by mixing a pigment, at least one selected from the group consisting of glittering pigment including aluminum powder pigment or pearl pigment; an opaque pigment including tin oxide, and alkylene bis(melamine) derivatives; and an opaque plastic pigment.
The aqueous ink composition with metallic glittering of the present invention also uses a colorant form of pigment dispersion liquid to control various ink colors. Wherein, the colorant is preferably a high-solubility colorant, which does not react to the metal-coating resin component, and does not affect the coloring of the metal-coating resin component. The embodiment example of the colorant comprises water-soluble dye such as acidic dye, directive dye, and basic dye; inorganic pigment such as carbon black and tin oxide; fluorescent pigment; and coloring resin emulsion etc. The amount of the colorant is 0.01 to 30 wt %, more preferably 0.05 to 20 wt % relative to total ink composition.
Also, the present invention uses water-soluble resin, preferably water-soluble thickening resin, which is capable of easily dispersing the metal-coating resin component and preventing precipitation thereof. The embodiment of the water-soluble resin comprises microbial polysaccharides and derivatives thereof such as pullualn, xanthan gum, whelan gum, rhamsan gum, succinoglucan and dextran; water-soluble vegetable polysaccharides and derivatives thereof including tragacanth gum, guar gum, tara gum, locust bean gum, ghatti gum, arabinogalactan gum, gum arabic, quince seed gum, pectin, starch, psyllium seed gum, carrageennan, alginic acid, argar etc.; and water-soluable animal polysaccharides and derivatives thereof including gelatin, casein, and albumin. More preferably, the microbial polysaccharides and derivatives thereof may be used either alone or in a mixture of more than two. The amount of the water-soluble resin is used 0.01 to 40 wt %, preferably 0.05 to 20 wt % relative to total ink composition.
Also, the ink composition of the present invention uses a water-soluble solvent in order to dry the pen tip and prevent freezing of ink. The embodiment of the water-soluble solvent is at least one selected from the group consisting of glycol such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and polyethylene glycol; polyvalence alcohol such as glycerin; and glycol ether such as ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether and dipropylene glycol monopropyl ether. The amount of the water-soluble organic solvent is preferably used 1.00 to 40 wt %, more preferably 5.00 to 20 wt % relative to total ink composition.
Moreover, the remaining component in the ink composition of the present invention comprises ion exchange water. As necessary, lubricants may be added, such as dicarboxylic amides, polyoxyethylene alkali metal salts, phosphates and N-oleyl sarcosine salts etc.; rust-inhibitors such as benzotriazole and tolytriazole dicyclohexyl ammonium nitrate etc.; antiseptic mildew-proofing agents such as benzoisothiazolin-type, pentachlorophenol-type and cresol etc.; and various surfactants.
The aqueous ink composition with metallic glittering of the present invention may be prepared by a conventional dispersing method, degassing techniques, filtering methods etc., the present invention is not limited to the methods.
As mentioned above, the aqueous ink composition with metallic glittering according to the present invention may be used in a variety of applications, as the aqueous ink composition with metallic glittering for writing tools (preferably an aqueous ink composition with metallic glittering for ball-point pens), printing, coating, and cosmetic etc. due to having an excellent luster, and three-dimensional effect.
Hereinafter, the present invention is described more in detail through Examples and Comparative Examples. However, the following Examples are only for the understanding of the present invention, and the present invention is not limited to the following Examples.